She was taken to the Mater Hospital at 3am on Saturday but died on Sunday.

A source told the Herald how staff at the Mater became suspicious after a large number of people were admitted in the early hours of Saturday.

“Seven people, including Ms Hick, were taken to the Mater Hospital on Saturday morning. Her friends told authorities that she had taken three tablets,” the source said.

“A member of staff at the hospital then contacted gardai saying it was no coincidence that so many people were admitted to the hospital on the same night, and a nurse suggested there was a correlation between Ms Hick and the other six people falling ill.”

The six young people have since fully recovered.

In an undercover operation carried out by officers stationed at Store Street on Saturday night, gardai arrested a male near the club on suspicion of selling illegal drugs.

The man, aged in his mid-20s, is believed to have offered drugs to the undercover detectives who subsequently searched him and found him to be in possession of several Class A drugs.

A later search of his Marino home found a large quantity of cash, ecstasy tablets and mixing agents used to manufacture several different types of illegal drugs including Ketamine and MDMA.

Dublin teenager Ana Hick

The operation took place less than 24 hours after Ana and the six others fell ill.

At 2am on Sunday a young male, who had been in the Twisted Pepper club, was admitted to the Mater Hospital with a suspected drug overdose, showing similar symptoms to Ana’s. He has also recovered.

Detectives are investigating the circumstances surrounding Ana’s death and are awaiting the results of toxicology tests.

Ana was remembered as a caring and loving girl, talented, popular and full of life at her funeral.

Her mother, Elga, supported by her dad, Tim, spoke bravely and eloquently of her only child.

“Ana was larger than life. She came smashing into Tim’s and my life like a comet and she was welcomed immediately into our lives,” she said.

Fr Patrick Devitt added: “Her short life was like a comet that lit up the sky and then left us.”

He said Ana had been christened and made her communion in the same church and invited mourners not only to weep for her but to laugh for her too as she “goes home to heaven”.

The youngest son of the late broadcaster Gerry Ryan helped carry the coffin of his friend Ana to her final resting place.